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2. Influence of phosphorus on gas exchange and plant growth of two morphologically distinct types of Capsicum annuum
- Creator:
- Davies, F. T., Duray, S. A., Phavaphutanon, L., and Stahl, R. S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Multiple languages
- Description:
- Tolerance to phosphorus stress was studied in Capsicum annuum L. Chile ancho cv. San Luis and bell pepper cv. Jupiter plants. Plants were fertilized weekly with Long-Ashton nutrient solution (LANS) modified to supply 0, 11, 22, 44, 66, or 88 g(P) m-3 (P0, P11, P22, P44, P66, P88). Phosphorus stress occurred in both cultivars at P0 and P11, with reduced plant growth and development. At P0, the lowest percentage of total biomass was directed toward reproductive growth. The root/shoot ratio was greatest at P0, reflecting greater dry matter partitioning to the root system. Growth of 'San Luis' was more sensitive to phosphorus stress than 'Jupiter'. A greater percentage of total biomass was directed towards reproductive growth in 'Jupiter' than 'San Luis'. Increasing P nutrition elevated leaf tissue P in both cultivars with highest leaf tissue P at P88. There were no differences in tissue P between P0 and P11 'San Luis' plants, whereas P0 'Jupiter' plants had the lowest tissue P. Low P-plants generally had the highest tissue N and lowest S, Mn, and B. In both cultivars, gas exchange was lowest at P0, as indicated by reduced stomatal conductance (gs) and net photosynthetic rate (PN). Internal CO2 concentration and leaf-to-air vapor pressure difference (VPD) were generally highest with P-stressed plants. Phosphorus use efficiency, as indicated by PN per unit of leaf tissue P concentration (PN/P), was highest at P11. Generally, no P treatments exceeded the gas exchange levels obtained by P44 (full strength LANS) plants. Both PN and gs declined during reproductive growth in 'San Luis', which fruits more rapidly than 'Jupiter', whereas no reduction in gas exchange occurred with 'Jupiter'. and F. T. Davies ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Italská cesta Julia Zeyera 1883 - 1884
- Creator:
- Stejskalová, Anna
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Margaritaella gracilis gen. n. et sp. n. (Eucestoda: Proteocephalidea), a parasite of Callichthys callichthys (Pisces: Siluriformes) from the Paraná River basin, Argentina
- Creator:
- Arredondo, Nathalia J. and Gil de Pertierra, Alicia A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Proteocephalinae, taxonomy, morphology, catfish, Callichthyidae, and Neotropical region
- Language:
- English
- Description:
- Margaritaella gracilis gen. n. et sp. n. (Proteocephalidea: Proteocephalinae) found in the intestine of Callichthys callichthys (Linnaeus) from the Paraná River basin is described. The new genus is placed in the Proteocephalinae because of the medullary position of the genital organs. It differs from all known genera included in the Proteocephalinae by the following combination of characters: 1) scolex with a conspicuous cluster of drop-shaped gland cells posterior to suckers; 2) strobila with a low number of proglottides, all much longer than wide; 3) testes arranged in one field, composed of two parallel rows of testes separated by the uterus; 4) ovary delicate, H-shaped, with branches slender and deeply folliculate at the edges, located at 25-35% from the posterior end; 5) uterus largely extended posterior to the ovary but not reaching the end of proglottis; and 6) vitelline follicles in two narrow lateral bands, largely extended posterior to the ovary. Scanning electron microscopy revealed three types of microtriches on the tegument surface: acicular and capiliform filitriches and gladiate spinitriches. The relative size of the ovary, a character recently used in the systematics of the proteocephalidean cestodes, was calculated for the new species and compared with other species of the group. M. gracilis is the first record of a proteocephalidean cestode parasitizing a callichthyid catfish.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Role of changing environmental parameters in leaf gas exchange of Arbutus unedo L. assessed by field and laboratory measurements
- Creator:
- Vitale, M. and Manes, F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- climate change, CO2 concentration, Mediterranean-type ecosystems, mesophyll conductance, net photosynthetic rate, physiological adaptation to stresses, respiration rates, ribulose-1; 5-bisphosphate carboxylase, oxygenase, stomatal conductance, and transpiration rate
- Language:
- Multiple languages
- Description:
- In the frame of the foreseen climate global changes we analysed the physiological responses of Arbutus unedo L. to the variations of carbon dioxide concentration, leaf temperature, and irradiance by measurements of leaf gas exchange and leaf water potential performed both in field and in the laboratory. Stomatal conductance was not affected by increase of leaf temperature. The growth conditions of potted plants likely made stomata more sensitive to the variation of external parameters than naturally growing plants. The interaction between high CO2 concentration and temperature involved important down-regulation mechanisms in the metabolic pathway of the carbon fixation. From an ecological point of view, the ability of A. unedo to adapt to the field stress makes it highly competitive in the Mediterranean plant community. and M. Vitale, F. Manes.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Three Dendromonocotyle species (Monogenea: Monocotylidae) reported from captive rays, including D. lotteri sp. n. from Himantura gerrardi (Elasmobranchii: Dasyatidae) in the public aquarium at the Atlantis resort, Dubai
- Creator:
- Vaughan, David B. and Chisholm, Leslie A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, Monocotylidae, Dendromonocotyle, public aquarium, Himantura gerrardi, Neotrygon kuhlii, and Dubai
- Language:
- English
- Description:
- Dendromonocotyle lotteri sp. n. is described from the dorsal skin surface of the stingray Himantura gerrardi (Gray) on exhibit in the public aquarium at the Atlantis resort in Dubai. It is differentiated from all other Dendromonocotyle species by the unique morphology of the distal portion of the sclerotised male copulatory organ. Dendromonocotyle lotteri is the second representative in the genus with 56 marginal haptoral papillae having a papillae to loculus association represented numerically as 6-6-8-8. We found Dendromonocotyle colorni Chisholm, Whittington et Kearn, 2001 on the same host specimens at the Atlantis resort public aquarium and Dendromonocotyle kuhlii Young, 1967 on Neotrygon kuhlii (Müller et Henle) kept at Burgers' Zoo Aquarium in Arnhem, The Netherlands. Supplemental information is provided for both D. colorni and D. kuhlii. The presence of Dendromonocotyle infections in public aquaria and host specificity are discussed. A key to the 17 species of Dendromonocotyle is also provided.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public